The name of the famous French cartomancer, Marie Anne Adelaide Lenormand (1772-1843), was first used in connection with the 36 card Petit Lenormand deck designed by Johann Kaspar Hechtel a few years after her death no later than 1846.
Such cards with a publication date of 1846 are included in a listing of new German publications as follows:
"Wahrsagerin, die, Mlle. Lenormand. Erklärung des Kartenspiels d. berühmten Wahrsagerin Mlle. Lenormand in Paris. Herausgegeben v. deren Erben Chator. 32. (36 illumin. Karten u. Text) Coblenz 846, Reiff. In Etui."
Neues Bücher Lexicon (Weigel, 1848)
This translates into English roughly as follows:
"Fortune-teller, Mlle Lenormand. Explanation of the card game of the famous fortune teller Mlle Lenormand in Paris. Issued by her heirs Chator. 32. (36 illuminated cards and text) Coblenz 846, Reiff. Cased."
You can see some images of such early decks dated c1846/7 in the Lenormand Museum here and here.
Wolfgang Kunze of spielkartenonline kindly provided me with the images included in this post of such a deck missing two cards sold by him and gave me permission to publish them for which I am very grateful:
(Click on the images to enlarge.)